1. Field of the Invention
This invention relates to an oxygen mask. More particularly, it relates to an oxygen mask having an opening for oxygen intake and an opening for exhaled or discharged gases, often called respiratory gases.
2. Description of the Prior Art
For years research has been going on on how to monitor oxygen intake and carbon dioxide outake of a patient safely, comfortably and easily while he or she is under anesthesia. For example, U.S. Pat. No. 1,926,027 describes a breathing apparatus which has a tubular connection 3 with a relief port 4. U.S. Pat. No. 2,248,477 concerns an inhalator mask which has an inner chamber in gaseous communication with an outer chamber. U.S. Pat. No. 2,795,223 describes apparatus made up of a tube having a mouthpiece, the tube also having a by-pass duct communicating with a chamber. In U.S. Pat. No. 4,201,205 is disclosed use of non-elastic flexible tubing which extends over and around the user's ears and under his chin. U.S. Pat. No. 4,258,710 involves a respirator which has holes in the side of a mask and a cup in front with an opening including valve means having an outlet into the interior of the mask. In U.S. Pat. No. 4,328,797 is described a mask which is adapted to provide for the passage of a tube therethrough. U.S. Pat. No. 5,005,571 involves a mouth nose mask having breathing monitor or the like apparatus mounted on a patient's face independent of a nasal cannula and over the cannula without impeding its function. U.S. Pat. No. 5,046,491 deals with collection and transportation separately or simultaneously of gases inhaled or exhaled via a patient's mouth during anesthesia or the like, using a nasal gas cannula and an oral gas capture member. None of the foregoing art solves the problem of how to monitor the breathing of a patient under anesthesia substantially without discomfort to the patient or problems during monitoring.